Dry goods bulk trailers are commonly used for transporting various forms of fluidic dry goods, for example grains such as wheat or barley or various other forms of particulate material such as fertilizer, salt, and the like. The typical construction of a dry goods bulk trailer includes a main frame assembly and a containment structure incorporated onto the frame. A typical containment structure includes upright side walls spanning the length of the trailer. One or more discharge hoppers are typically connected between the side walls at a central location to form the bottom side of the containment structure. A front slope wall and a rear slope wall are connected between the side walls at opposing front and rear ends so as to taper downwardly and longitudinally inwardly towards the central discharge hoppers.
Each slope wall is typically formed of one or more sheets of material which are joined together in a single layer to be connected between the side walls of the containment structure. Rivets are the preferred type of fastener for joining multiple sheets at the seams thereof. The sheets of material are typically formed of aluminum when used for transporting grains and the like. To provide added structural support to the single layer of sheeted material, typically a plurality of crossbars are provided to span the bottom side of the sheet layer in a lateral direction between the opposing side walls so as to be spaced apart at longitudinal intervals relative to one another. The single layer of sheet material forming the inner surface of the slope wall is typically joined to the crossbars using rivets or other similar fasteners due to the inability to weld aluminum to the structural members typically formed of steel. Due to the large number of fasteners required for joining sheets at respective seams and for joining the sheets to the crossbars, the resulting inner surface is interrupted by numerous protruding fastener heads upon which transported material can be caught such that the containment area is difficult to fully clean out even after the majority of material has been discharged through the bottom discharge hoppers.
A further problem arises due to the location of the crossbars which form a shelf at the exterior bottom side of the slope walls upon which road debris can become entrapped. Intermediate posts are typically also required to support the crossbars relative to the frame which add to the problem of debris collection thereon. Particularly, snow and slush are known to be collected on the crossbars and support posts, which form ice on the bottom side of the slope walls in colder climates, resulting in undesirable added weight to the trailer, which in turn limits the cargo carrying capacity. Despite the disadvantages of material collecting on the crossbars, the crossbars are typically found to be necessary for providing sufficient strength to existing slope wall constructions.